Gait is one of unique physical features of human beings and it is the most common exercise as well as the basic activity that humans perform every day.
In general, the gait cycle of normal people has the stance phase and the swing phase. Stance phase is the period when the foot is in contact with the ground and it consists of the initial contact step, the foot flat step, the mid stance step, the heel-off step and the toe off step. The swing phase is the period when the foot is off the ground and it consists of the toe off step, the mid swing step and the initial contact step. In normal gait, the stance phase accounts for approximately 60% of the gait cycle and the swing phase accounts for 40% of the gait cycle.
The gait training is a very important unit for patients with gait disorders who lose the gait ability in order to improve the level of independence and the quality of a good life.
Comprehensive assistance of many experts in multiple fields is required for the rehabilitation training to recover the gait ability of patients with gait disorders. In particular, repeated and systematic gait training is required to improve the sense of balance of patients and increase the tolerance of patients.
About 90% of patients with gait disorders are caused by the acquired gait disorders and 50% of acquired disabilities are caused by various diseases. Among them, the stroke accounts for the highest percentage. In the initial period after the occurrence of the stroke, it has been reported that 51% of patients cannot walk at all and 12% of patients can walk with assistance and 37% of patients can walk independently. After the rehabilitation treatment, 64% of patients are recovered to allow them to walk independently, but 36% of patients cannot walk or can walk dependently. Even if the gait function is recovered, abnormal gait patterns may be shown due to the disorders of various motor functions.
In particular, because the extent of possible walking varies depending on patients with gait disorders, the gait training using the patient's own remaining senses could produce a higher effect rather than the uniform gait training.
In order to do this, the accurate judgment on how much patients with gait disorders can currently walk is needed and the gait training based on this judgment is required.
In conventional cases, the gait level of patients with gait disorders was determined by the palpation of a therapist and by using the sensory stimulation.
In the middle of 1980s, the gait training on a treadmill through body weight support was proposed and it was reported that the treatment was clinically effective through this training.
However, the conventional cases had disadvantages in which a couple of therapists held the movement of limbs and trunk of patients with gait disorders and induced the gait while patients with gait disorders performed the training on treadmill.
Also, the passive gait training robot which passively moved the leg joint by the robot joint, was proposed for the elderly and the disabled. However, it was not accurately consistent with the gait path which a patient intended and the fundamental gait training for rehabilitation which satisfied the normal gait pattern could not be made.
Therefore, the gait training system is required in which active gait training is available and the joint movement optimal for normal gait pattern is provided by using the remaining senses of patients with gait disorders.
The present invention proposes the active robotic gait training system and method which estimates the gait cycle by measuring the slope of the lower legs, operates the hip joint and knee joint based on the gait cycle by an actuator, operates the ankle joint by functional electric stimulation (FES) and enables more active gait training based on remaining gait ability of patients with gait disorders.